La sterilità dei dispositivi monouso rigenerati. Studio su cateteri per cardiologia interventistica dopo riutilizzo simulato

The reuse of single use devices is of particular interest in interventional cardiology where the economic load of the devices represents a significant share of the whole procedure. The sterility of the reprocessed device must be tested and warranted, together with chemical-physical and functional performances. This study evaluates the efficiency and limitations of an experimental reprocessing protocol in order to assess the sterility of cardiac electrophysiology catheters and the maximum number of regeneration cycles sustainable by the device. A first lot of 54 devices, collected after clinical use in the Cardiology Department of S.Chiara Hospital in Trento, was reprocessed and tested for sterility. Devices underwent repeated cycles of simulating-use (bacteria spiked blood) and regeneration (decontamination, cleaning and hydrogen peroxide gas plasma sterilization): 36, 24, 28, 35, 22 devices were regenerated respectively 2, 3, 4, 5 and 6 times. Entire devices were cultured for 28 days in trypticase soy broth. On the whole,we tested 199 samples, six cycles of regeneration and four inoculation species. No positive sample to inoculated strain was found until the fourth cycle of reprocessing. The inoculated Bacillus subtilis strain was recovered in samples reprocessed five and six times. Reprocessing procedures following the adopted protocol turned out efficient to guarantee device’s sterility up to five reuses in experimental conditions representing the worst case scenario for bacterial load. However, complexity of reprocessing protocols, organizational issues, economic and legal requirements addressed to qualifying and certifying all steps of the reprocessing procedure discourage “in house” reprocessing.